Dragonflies are ideal hunting machines. More than 80 percent of their brain is used for processing visual information, and it is believed that some species can see objects up to 30 feet away and detect movement as far as 60 feet away.
And how do they direct these tremendous talents? Dragonflies hunt, and eat, a lot: They consume 10 percent to 15 percent of their own weight per day on insects such as mosquitoes, termites, deerflies, blackflies, horseflies and midges. They make welcome residents in the yard, as they'll keep it far less buggy. Think of it as the insect equivalent of getting a cat to solve your mouse problem.
If you want to attract dragonflies to your yard, the best lure is a body of water. Dragonflies lay eggs in or near water, where their young hatch and develop into nymphs. They live underwater for months and sometimes years before emerging as adults. But even as nymphs, they are voracious eaters, happily dining on mosquito larvae and other underwater creatures.
To bring in the dragonflies, you can either create a pond or make sure that the bodies of water near your property are dragonfly-friendly.
A pond doesn't need to be large, nor does it require a filter, but it does need several key features. It should be located in an area that is protected from wind but will get five or six hours of midday sun.
The depth should vary from very shallow at the edges to about 2 feet at its deepest level. A pond that is too shallow can overheat or dry up, and the deep areas provide refuge from predators like our dragonflies.
Put plants in and around the pond. Plants, both submerged and floating, add oxygen to the water and remove carbon dioxide. They provide hiding and resting places for nymphs and are used as incubation chambers, because some species insert their eggs into the soft stems.
Tall plants that stick out of the water provide places for adult dragonflies to perch and scan for food or mates. They also allow a place for the nymphs to climb up to undergo their transformation process from nymph to adult. Dragonflies must pump up their wings before they can be effective fliers, but they emerge with soft bodies. It takes several days before the wings harden completely and take on the colors of an adult dragonfly.
What you plant around the pond is also important. Dragonflies like to find an elevated perch from which they can keep an eye on their favorite feeding and breeding spots. They are aggressively territorial and will chase away or even do battle with their competitors. If you prefer, you can plant ordinary bamboo stakes near the pond. The insects will also appreciate a few flat rocks placed near the pond's edge, as rocks provide surfaces to bask in the sun.
If you want a pond that supports breeding populations of dragonflies, don't introduce fish, frogs, or ducks. These creatures will prey on the nymphs and eggs. And of course, keep all poisons and fertilizers out of the water.
Experts say that about 15 percent of North America's dragonfly species are in danger of extinction. Attracting dragonflies to your yard helps you do your part to protect these beneficial bug-zappers while cutting down on the bugs that really bug you.